Data Transfer Object classes should follow the name convention defined in the Java Language Specification:
Names of class types should be descriptive nouns or noun phrases, not overly long, in mixed case with the first letter of each word capitalized.
ClassLoader SecurityManager Thread Dictionary BufferedInputStream[…]
Suffixing a class name with DTO or Dto won’t tell much about the class itself besides indicating it carries data without any behaviour. So, instead of just calling your objects DTO, it might be worth considering more meaningful names, which convey better semantics for the classes.
Here is a non-exhaustive list of name suggestions you could use:
SomeSortOfCommandSomeSortOfConfigurationSomeSortOfCredentialsSomeSortOfDetailsSomeSortOfElementSomeSortOfEventSomeSortOfFilterSomeSortOfHeaderSomeSortOfInputSomeSortOfInstructionSomeSortOfItemSomeSortOfMessageSomeSortOfMetadataSomeSortOfOperationSomeSortOfOutputSomeSortOfPayloadSomeSortOfProjectionSomeSortOfPropertiesSomeSortOfQueryParameterSomeSortOfQueryResultSomeSortOfRepresentationSomeSortOfRequestSomeSortOfResourceSomeSortOfResponseSomeSortOfResultSomeSortOfRowSomeSortOfSettingsSomeSortOfSpecificationSomeSortOfStatusSomeSortOfSummary
Note 1: Whether acronyms or all capitalized words should be handled as words or not, I guess it’s up to you. Check the Java API and you will find some stumbles like ZipInputStream / GZIPInputStream. Both classes are in the same package and the name convention is not consistent. HttpURLConnection doesn’t show any consistency with acronyms either.
Note 2: Some names listed above were borrowed from this article written by Richard Dingwall (the original article seems to be no longer available, so here’s a cached copy from Web Archive).